For DNA-methylation to act as a mechanism of inheritance, variations in methylation patterns must be reliably transmitted over generations. Here we test whether DNA-methylation acts as an inheritance mechanism in Daphia magna, a clonally reproducing crustacean. We induced developmental stress using four different treatments (5-azacitidine, zinc, microcystin and elevated water temperature) to test (i) if stressors induce consistent or stochastic changes in DNA methylation across the genome, and (ii) if induced DNA methylation variants are transmitted to consecutive generations. All stressors reduce fitness in the first generation, which took up to four generations to recover. This can either be the result of maternal effects (such as egg size) or transgenerational effects. The effects were particularly strong for 5-azacitidine, which acts as an inhibitor of DNA methylation.
Currently SciLifeLab is performing whole genome bisulphite sequencing from genetically identical lineages exposed to the different stressors and controls across four generations. Because, we cannot pool individuals for this project and the amount of DNA per individual is small, SciLifeLab is testing a novel library preparation method - SPlinted Ligation Adapter Tagging (SPLAT) - on some of our test samples. I wish to use the Uppmax facilities to first analyse the data from the test sequencing and when the results are satisfactory also for data which will be produced by the sequencing of our experimental samples.